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Reverting to Type

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A view of the enclosure after 7 growing seasons – heather patchy inside, microscopic without, but now uneaten grasses inside are start to swamp new growth

One of my first experiments on beginning Working for Grouse was to fence off a small area of heavily overgrazed heather on the hill. I called this my “heather laboratory” – it was less than half an acre and initially taught me more about fencing than it did about botany, but with benefit of six years (seven growing seasons) of hindsight, there have been some really useful lessons to come from this little project.

  • Cottongrass bounced back within weeks. The show of cottongrass fruits (white bobbles) was exceptional in year one and has been declining ever after. This was an indication that i) the sheep were exerting a serious pressure on cottongrass flowers in March and ii) in common with many other grasses, cottongrass seems to be invigorated by grazing and becomes less productive without livestock.
  • Flowering plants like bog asphodel, bedstraw and tormentil did very well until choked out by grasses which really came into their own in year 5 and 6. Several species of lichen prospered in the early days, and some of these have been able to sustain dominance.
  • After decades of overgrazing, the heather showed almost no improvement in year 1. It’s almost as if it needed an entire growing season to “catch its breath” and regroup. When it did begin to grow, it picked up pace which accelerated inconsistently within the margins of successive good and bad growing seasons.
  • Moss (not sphagnum species, but dry mosses) prospered and grew at a surprisingly brisk rate. As the heather grew, it provided a scaffolding for moss which climbed up beneath the heather canopy until heather plants simply became large tussocks of moss decorated with a few growing sprigs of heather. After 7 growing seasons, some of these tussocks are now twelve inches deep or more, almost totally burying the heather plants. This moss was a revelation because it does not prosper in any meaningful way outside the enclosure because i) the heather is not big enough to provide scaffolding for growth and domination, ii) moss is repeatedly trampled and kept in check by sheep and cows, and iii) some of these mosses are eaten by sheep in the worst days of winter.
  • Sitka spruce scrub began to appear in year 2. Some trees are now almost a foot high.
  • Heather beetle struck the heather in year 4 and 5, killing many of the resurging heather plants. It is likely that heather beetle has been part of this property’s story for many years, and almost immediately the uniform carpet of heather was broken into patches. Deep moss growth beneath heather plants meant that there has been almost no regeneration from roots. Beetle grumbled on in years 6 and 7, scarring the heather and making it tufty. Recovery was not great, and much of the heather looks tatty in the “lollipop” style.
  • It is now apparent in year 7 that grasses are beginning to dominate. The patch actively requires livestock to maintain a healthy balance of grass and heather. Even deer grass is building into mats which will soon be too thick to allow growth from seed. Molinia (purple moor grass) is beginning to get a hold here and there, posing a threat to the future viability of heather coverage.

 

In the grand scheme of things, heather moorland is an unnatural ecosystem. In many (but not all) cases, heather fills the gap during a transitional phase as habitats revert into woodland. Humans keep moorland in this early phase because it provides us with all kinds of benefits, including biodiversity and agricultural potential. I am watching these first stirrings of change in this little enclosure, and the results are fascinating as various species rise and fall in their ability to dominate the natural resources.

Most compelling of all, the experience is teaching me that moorland is not an easily defined habitat. On the East coast, moors are defined by wall-to-wall heather – the kind of ground which riles up anti-grouse shooting enthusiasts with accusations of “monoculture!” In reality, this is just a kind of dry, heather-friendly moorland which lends itself particularly to the production of grouse. This ground also owes part of its success in productivity to a meteorological quirk which has rendered the East coast better suited to the production of small, rain-sensitive chicks.

It seems that moorland in Galloway (at least in the early 21st Century) is a grassier, more varied blend of species with heather on the back foot, fighting to stand still in a world of grass. This much is obvious in the Galloway hills a few miles further West, most of which run very green in summer and then white in winter. This boggier, peatier kind of ground is less ideally suited to grouse, but because it is grassier it tends to be very popular with voles and pipits, which then encourage specialized predators like harriers, short eared owls – all fine by me.

From a black grouse perspective, the grassy blend is ideal – some of the best black grouse habitat (and particularly breeding habitat) I’ve seen is made up of this kind of scruffy, rushy, heathery blend. Perhaps one of the major changes in the 20th Century is that Galloway (which once described itself as the “land of birch and rowan tree”) now fails to produce much native broadleaf scrub when grazing pressure is relieved. Instead, idle ground soon finds itself with a thin stubble of self-sown sitka spruce. For every birch that has grown on the big hill since our fires in 2012, twenty spruces are now coming through, and this is a serious issue for the long term preservation of open ground.

Moorland is a many-faceted habitat, with wide variation even within Scotland. I look forward to the future of this little enclosure, which has repaid in knowledge the effort of building it many times over.

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